P40 Is routine liver function testing necessary for patients receiving latent tuberculosis treatment

IntroductionTuberculosis was the leading cause of mortality from infectious disease until the covid-19 pandemic. Over a quarter of the world’s population is estimated to have latent tuberculosis infection (LTBI), with 5–10% expected to develop active TB. Hepatotoxicity is a well described side-effect of anti-tuberculosis medication, often leading to disruptions in treatment. Currently, NICE guidelines recommend careful liver function test (LFT) monitoring of patients on anti-tuberculosis medication with liver disease, abnormal baseline LFTs or with history of alcohol or hepatotoxic drug misuse. However, there is no specific guidance on LFT monitoring for routine treatment.MethodsAll patients with LTBI in a single centre were identified from hospital records over a 3-year period (January 2018-December 2020). Clinical notes and blood test results were analysed for all patients, identifying any drug induced liver injury (DILI). Frequency and timing of LFT monitoring once starting treatment was reviewed and correlated with patient symptoms.ResultsOver a 3-year period, 180 patients received treatment for LTBI. 169 patients (94%) had baseline LFTs measured. 7 patients (3.9%) had deranged LFTs during their treatment, with 3 (1.7%) meeting the criteria for DILI. 2 of the 3 patients (66%) with DILI were symptomatic prompting blood tests, 1 patient (33%) had abnormal baseline LFTs. Of the 7 patients with LFT derangement during treatment, 4 (57%) had deranged baseline LFTs, 4 (57%) were symptomatic. Only 1 patient had neither symptoms nor abnormal baseline LFTs, but had abnormal baseline renal function requiring regular monitoring.ConclusionsThese results suggest that risk of DILI is present but relatively low in patients receiving treatment for LTBI. Most patients from this cohort with DILI were either high risk as per NICE guidance or symptomatic prompting LFT checking. Therefore, routine monitoring of LFTs for all patients on LTBI treatment is unlikely to be cost-effective or change treatment outcomes. Instead, LFT monitoring should be considered specifically for patients that are high risk or with symptoms of DILI.ReferencesNational Institute for Health and Care Excellence (NICE) (2016) Tuberculosis. Available at https://www.nice.org.uk/guidance/ng33Global tuberculosis report 2020. Geneva: World Health Organization;2020. Licence: CC BY-NC-SA 3.0 IGO.